set_cover

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description states the tool materializes files and writes post.cover, which is a destructive action. However, annotations set destructiveHint=false, creating a contradiction. The description does not reconcile this, so transparency is poor.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is composed of two long sentences that are dense but clear. It front-loads the main action and includes all necessary information without excessive verbosity. Minor improvement could be splitting into shorter sentences.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool has 6 parameters (2 required) and no output schema, the description fully explains the action, parameter roles, side effects (file materialization), and return value (applicability map). It leaves no critical gaps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, and the description adds value by explaining usage contexts for frameSec, filePath, and base64, including a size constraint. It clarifies the relationship between parameters and the cover source.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool sets a cover override for one post, listing three methods (frameSec, filePath, base64). It is specific and distinguishes it from siblings like 'clear_cover'.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explains when to use each method (e.g., extract frame from media, upload local file, or base64 bytes). It implicitly guides the agent on selection but lacks explicit exclusions or when-not-to-use guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.